FOUR THINGS ABOUT GHOST OCTOPODS

1 WHY ARE THEY CALLED GHOSTS?

Explorers with the U.S. National Oceanic and Atmospheric Administration’s Okeanos team discovered the creatures 4,000 metres deep in the ocean. “This animal was particularly unusual because it lacked the pigment cells, called chromatophores, typical of most cephalopods, and it did not seem very muscular,” wrote the NOAA’s Michael Vecchione. “This resulted in a ghostlike appearance, leading to a comment on social media that it should be called Casper, like the friendly cartoon ghost.”

2 WHAT AND WHERE ARE THEY?

The animal was “almost certainly” a species heretofore unknown to science, Vecchione said, and may even belong to a new genus. Remote video surveys conducted between 2011 and 2016, off the Hawaiian Archipelago and in the Peru Basin to the south of the Galápagos Islands, found several ghost octopods.

3 WHAT MAKES THEM UNUSUAL?

Lumps of manganese slowly accrete like pearls in place along the sea floor. In certain places, the clumps form vast fields. Some nodules may reach the size of bowling balls. German and American scientists observed Casper-type octopods living among the manganese nodes. The Pacific octopods also displayed a particular egg-laying behaviour. The scientists witnessed two animals clinging to dead sea sponges, which in turn were anchored to manganese nodes, giving mother octopods a stable place to guard their clutches.

4 MINING COULD BE A PROBLEM

The United Nations approved deepsea manganese prospecting permits in 2014. “The brooding behaviour of the octopods we observed suggests that, like the sponges, they may also be susceptible to habitat loss following the removal of nodule fields and crusts by commercial exploitation,” the scientists concluded.